Seasonal Variation in Nearshore Wave Characteristics off Cuddalore, Southeast Coast of Tamil Nadu, India

Abstract

Wave data collected using wave rider buoy between January 2010 and January 2011 off Cuddalore coast, Tamil Nadu, India, have been analysed season-wise in this study. Wave steepness method was used for the separation of sea and swell wave parameters. Also parameters such as significant wave height of total wave, sea and swell (H s , H sw and H ss ), zero crossing periods (T z , T sw and T ss ) and mean wave directions (θ, θ sw and θ ss ) have been studied. The study shows a distinct shift in sea wave direction of about 90° between June and October as well as November and February. Throughout the year, the predominant swell direction remained around 135°. The contribution in total H s by H sw was 76% and the remaining 24% by H ss in the yearly cycle. The sea wave height was dominant by more than 90% during November to May. Regression analysis showed good positive Pearson's correlation of 0.94 between Hs and H sw ; however, it was 0.65 between H s and H ss . The maximum and significant wave heights of 5.7 and 2.7 m were recorded during cyclone Jal on 7 November 2010.